Earnshaw's theorem implies that it is impossible to achieve stable static magnetic levitation in a static magnetic field. However, the discovery of the Levitron™ has shown that it is in fact possible for a spinning top to be in stable equilibrium in a static magnetic field. This phenomenon, referred to herein as spin-stabilized magnetic levitation has been widely analyzed in the literature. The Levitron™ itself is described in U.S. Pat. No. 5,404,062, incorporated herein by reference. In general, in conventional spin-stabilized magnetic levitation devices such as the Levitron™ the rotational (spinning) motion of the rotor overcomes lateral instability of the rotor in the magnetic field. The conventional spin-stabilized devices are axisymmetric, and are limited to rotation about a vertical axis, that is, an axis aligned with the direction of the force of gravity.
It is desirable in view of the foregoing to provide for spin-stabilized magnetic levitation that does not require alignment of the rotational axis with the direction of the force of gravity.
Exemplary embodiments of the invention use the symmetry properties of a magnetic levitation arrangement to produce spin-stabilized magnetic levitation without aligning the rotational axis with the direction of the force of gravity. The rotation of the rotor stabilizes perturbations directed parallel to the rotational axis.